Incorrect Authorization Affecting github.com/mattermost/mattermost/server/channels/api4 package, versions <10.11.11>=11.2.0-rc1 <11.2.3>=11.3.0-rc1 <11.3.1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-GOLANG-GITHUBCOMMATTERMOSTMATTERMOSTSERVERCHANNELSAPI4-15702111
- published20 Mar 2026
- disclosed16 Mar 2026
- credit0x7oda7123
Introduced: 16 Mar 2026
NewCVE-2026-4265 Â (opens in a new tab)How to fix?
Upgrade github.com/mattermost/mattermost/server/channels/api4 to version 10.11.11, 11.2.3, 11.3.1 or higher.
Overview
Affected versions of this package are vulnerable to Incorrect Authorization via the upload process. An attacker can bypass team-specific file upload restrictions by uploading files in a team where they have permission and reusing the file metadata in a POST request to a different team.